OBJECTIVES: In patients with lumbar spinal stenosis (LSS) undergoing unilateral biportal endoscopic unilateral laminotomy for bilateral decompression (UBE-ULBD), damage to the epidural venous plexus often leads to bleeding, increasing the risk of surgical complications. Surgiflo Hemostatic Matrix (SHM) is a gelatin extracted from porcine skin, used for intraoperative hemostasis. This study aims to evaluate the effectiveness and safety of using SHM during UBE-ULBD surgery. METHODS: From October 2023 to July 2024, a total of 96 patients with LSS underwent UBE-ULBD surgery. These 96 patients were randomly divided into two groups: the SHM group (48 patients, using flowable gelatin) and the non-SHM group (48 patients, not using flowable gelatin). The primary outcomes included intraoperative blood loss, postoperative drainage volume, and the 3-min hemostasis success rate. Secondary outcomes included symptomatic postoperative epidural hematoma (SPEH), surgical time, postoperative hospital stay, hospitalization costs, and complications. We used independent sample t-tests to compare continuous data, and chi-square tests or Fisher's exact tests to analyze categorical data. RESULTS: The intraoperative blood loss and postoperative drainage volume in the SHM group were significantly less than those in the non-SHM group (p <
0.05), and the 3-min hemostasis success rate in the SHM group was significantly higher than that in the non-SHM group (p <
0.05). There were no statistically significant differences between the two groups regarding SPEH, postoperative hospital stay, hospitalization costs, and complications such as thrombosis formation and allergic reactions. However, the surgical time in the SHM group was significantly shorter than that in the non-SHM group (p <
0.05). CONCLUSION: When patients with LSS undergo UBE-ULBD, the use of fluid gelatin can effectively reduce intraoperative and postoperative bleeding without introducing additional complications.